The revolution of 1795 in the Republic of the Seven United Pro-
vinces and the European war affected the events and status of the
Dutch colonies. The island of CuraCao, the most important of the
Netherlands Antilles, was no exception and experienced a series
of internal changes and finally even a change in colonial masters
when it was conquered by Great Britain in 1800 and again in
1807. One of the most dramatic internal episodes occurred in
September 1799 when the colonial government of Curagao
expelled a French citizen, Jean-Baptiste Tierce, for his alleged
participation in a conspiracy and plot against the authorities.
After his expulsion, Tierce's ordeal was not over since he was in-
carcerated in the Batavian Republic where he had hoped to obtain
justice. While the events of Tierce's arrest and expulsion are well
known, his imprisonment in the Netherlands and its diplomatic
repercussions have not been given any attention. This article will
attempt to present an account of Tierce's experiences in the Bata-
vian Republic in 1800 and 1801.

Curacao had been a Dutch colony since 1634 and like other Euro-
pean colonies in the West Indies relied heavily on the institution
of slavery to sustain its economy. In 1789 the number of slaves
was 12,804 as opposed to 3964 whites and 2776 free colored. On
the island also lived a large number of other Europeans besides
the Dutch such as some 400 French citizens. Partly as a result of
the impact of the French Revolution and the slave revolt in French
Santo Domingo an insurrection among the slaves occurred in
August 1795. It failed, however, and the leaders were executed.
News of the flight of Stadholder William V reached Curacao on
May 16, 1795, but the old colonial government remained in
office much to the chagrin of the Patriotic elements. On August
10, 1796, it became known that the stadholderate had been
abolished, and, therefore, no one would henceforth be bound by
the oath of loyalty. The officials swore their allegiance to the
Batavian regime, and a new director ad interim, Jan Jacob Beau-
jon, was appointed whileJohann R. Lauffer became the comman-
der of the national guard. Soon Beaujon and Lauffer disagreed
over such matters as defense, and the former was forced to resign
in December 1796 to be replaced by his rival. 1
1

G.D. HOMAN

Lauffer was born in Switzerland and had come to Curagao as a
soldier in 1776. He earned the respect of many of the local inha-
bitants and sided with the advocates of change although he was
not a radical. His task was not simple since he not only had to
watch the enemy, the British, but also his allies, the French, who
were perhaps more of a threat to the island. The French Republic
had dispatched many agents to the Caribbean some of whom
were most anxious to establish a French regime in Curacao. With
the growing chaos in Santo Domingo the number of French refu-
gees increased, and Lauffer realized that they might pose a poten-
tial threat to his administration.

Among the well established French citizens in Curagao wasJean-
Baptiste Tierce. He was born in Le Havre in 1754 and came to the
island in 1784.2 In the course of time Tierce accumulated 'a small
fortune and credit.'3 He was widely respected in the business
world4 and by others and played an important role in his local
Catholic Church where he served as eerste kerkmeester. 5 He also
assisted in the suppression of the slave revolt in 17956 and he
supported the Patriots. He and others demanded in September
and December 1796 to place Captain First Class, Albert Kikkert,
and Lauffer in charge of the defense of the island since Beaujon
seemed not aggressive enough to prepare the island for a possible
outside attack.7 He also attacked Rear-Admiral Wiertsz even ac-
cussing him of treasonable conduct since the latter had allegedly
once agreed to surrender Willemstad to the British. Wiertsz was
furious over the accusation and complained to the colonial coun-
cil 'how slanderous, how dishonorable, how grievious' a certain
Tierce had dared to accuse him.8
On July 3, 1796, Tierce was appointed to fulfill the French con-
sular function relative to the sale of prizes on the island of Cura-
cao. On September 10, 1798, he was appointed receveur of
French prizes which entitled him to keep 5% of the receipts. His
consular activities were terminated in April 1798, and in June
1799 Tierce was replaced as receveur by General Urbain Devaux.9
A few months later Tierce was imprisoned and deported for par-
ticipation in a plot against the colonial government.

Why Tierce became the principal ringleader of this cabal against
Lauffer's administration is not clear. He had once been an active
supporter of the director and even supported his appointment.
Lauffer alleged once that Tierce had since 1796 thwarted the

JEAN-BAPTISTE TIERCE AND THE BATAVIAN REPUBLIC 3
government in every possible way and spread 'the most infamous
lies' about the Curagao government among the neighboring
French possessions. 10 There is no evidence to support that accu-
sation, however. It is possible that Tierce was politically naive and
was persuaded by frustrated and disgruntled French refugees to
overthrow Lauffer's government and to install Kikkert who was
more pro-French. The available evidence seems to indicate that
Kikkert, who was no friend of Lauffer, played a somewhat sinister
role in this affair. He undoubtedly had secret ambitions to be-
come director of the island, a position he finally obtained in1815.
Furthermore, he and Tierce were and remained close friends even
after the disaster of September 1799.11
It is not clear when the first rumors of a plot against his admini-
stration reached Lauffer. Later he contended that his enemies
would have tried to stage a coup d'itat as early as 1797, but fear
of Rear Admiral Wiertsz caused them to hesitate. After the
latter's death in October 1798 the cabal became bolder and sear-
ched for a suitable leader. 12 In August 1799 Lauffer informed the
Committee for the Affairs of the Colonies and Possessions of the
Batavian Republic in America and the Coast of Guinea that the
National Guard had enabled him 'to foil completely all the at-
tempts by the still active cabal.'13 However, on September 8 he
reported to his Colonial Council in Curacao that he had received
significant information about a plot led by General Devaux
against his government. Apparently, the original plot had called
for an expedition to be launched from Santo Domingo, an under-
taking for which the leader of the slave revolt in that French colo-
ny, Toussaint l'Ouverture, would furnish ships and men. How-
ever, the plan was changed, and it was decided to stage a coup
d'itat against Lauffer who would be replaced by Kikkert. One of
the first acts of the new government would be the freeing of the
slaves. If the plot had succeeded, Lauffer wrote, 'this most
terrible undertaking' would have resulted in 'a most horrible
massacre' and Curacao and the entire West Indies might have
shared the fate of Santo Domingo. 14
The Colonial Council of Curagao was impressed with Lauffer's
evidence and ordered the immediate arrest and deportation of
General Devaux. The latter vigorously denied any complicity in
the plot, 15 and most likely he was only marginally involved.
Lauffer himself wrote later that Devaux was not a man with an
'evil heart' but had a rather 'fiery imagination' and was 'imma-
ture' in his opinions.16

4 G.D. HOMAN
A few days later Lauffer concluded, however, that not Devaux
but Tierce had been the principal ringleader, and on September 13
he requested the Colonial Council to order his arrest, a request
that was promptly granted. Furthermore, it was later revealed
that Tierce had been in secret communication with Spanish rebels
from Caracas and had even helped one of them, a certain Pedro
Cannibens, to escape.17 The Colonial Council searched Tierce's
house on September 18 but could find no incriminating evidence
except for some papers that tended to prove that he had been
active for some time in stirring up the French authorities against
the government of Curacao. 18 Tierce's priest, Jacobus Schinck,
tried desperately to testify on Tierce's behalf, but the Colonial
Council could not be persuaded, and on September 26 ordered
his expulsion from the island within eight days. 19 Tierce left the
island on October 7. He had barely time to arrange his private
affairs and begged a friend to care for and have mercy on his
children and their mother. 20

Tierce went first to Spanish Santo Domingo and then to Cap
Francais where he boarded a French ship bound for Bordeaux.
However, this vessel was seized by an American frigate and
brought first to Newport and later to Boston. Here he boarded
the Mahale Winsor bound for Rotterdam where he arrived on
May 11 or 12, 1800. In the Batavian Republic he hoped to be
given a chance to vindicate himself. Subsequently, he intended to
go to Paris to discuss his problems with the minister of navy and
colonies.21
With Tierce from Curacao to Boston and to Rotterdam
travelled another inhabitant of Curacao, Jan Hendrik Quast,
Quast was a young naval officer and the son ofJohan Caspar
Adolf Quast, the late pastor of the Protestant congregation in
Curacao. He had not been involved in the cabal against Lauffer
although he and Tierce seemed to have been close friends. Quast
claimed he was simply travelling to Europe to settle some of his
business affairs after which he intended to return to Curacao
where his wife and children still lived.22
Upon his arrival in the Batavian Republic Tierce soon learned,
especially from Hubertus Coerman, a member of the Committee
for the Affairs of the Colonies, that the authorities had been fully
informed about the events of September 1799. Thus he soon
realized he could not expect to receive a sympathetic or unbiased
hearing, and resolved to go to Paris.2 3

JEAN-BAPTISTE TIERCE AND THE BATAVIAN REPUBLIC 5
However, on May 19, the Agent of General Internal Police, A.J.
La Pierre, decided to arrest Tierce and Quast. During the interro-
gation in the days following Tierce vigorously denied any compli-
city in a plot to overthrow the government of Curacao. He did
acknowledge that he had had contact with Spanish rebels from
Caracas and at the request of Director Lauffer hid one in his
house. He was exiled, he charged, because Lauffer disliked him
since Tierce was a 'good friend' of Kikkert. Furthermore, he
added that the patriots in Curacao were dissatisfied with Lauffer
because he was despotic. Quast also denied any complicity
although it appeared that the French agent in Spanish Santo
Domingo had paid his travel expenses from Cap Francais to
France.24
Although the interrogation had not provided La Pierre with
anything very incriminating, th Agent resolved on June 6 to
request the UitvoerendBewindfor permission to hand over Tierce
and Quast to the judicial officials. The Directors readily agreed on
June 7 provided that the Legislative Body recognize the Court of
Holland and Zeeland's competence to prosecute the two men
who were allegedly guilty of crimes committed in the colonies. At
this time the Batavian government had not yet settled the question
if a person who had committed a crime in the colonies could be
tried by a court in the Republic. This problem was easily solved,
however, when the Legislative Body on June 26, 1800, passed a
decree empowering the Court to prosecute Tierce and Quast.25

By this time the case against Tierce and Quast had produced a
serious crisis in the Committee for the Affairs of the Colonies. On
June 6, while recommending Tierce and Quast's prosecution by
the Court, La Pierre also charged one of the members of the
Committee for the Affairs of the Colonies, Hubertus Coerman,
with improper conduct that warranted his temporary exclusion
from that body.26 Coerman once resided in Curagao where he
served as advocaatfiscaaland as a member of the grootenraad.27
Although he was living in the Batavian Republic in 1800, his wife
had remained in Curacao. He knew Tierce and also Quast and
these two men had immediately contacted him upon their arrival
in Rotterdam in May. Undoubtedly, Coerman sympathized with
the two men and divulged information to them, especially on
Lauffer's communication with the Committee for the Affairs of
the Colonies that he, as a member of that body, should have kept
confidential. La Pierre learned about Coerman's indiscretion

6 G.D. HOMAN
during the interrogation and demanded the latter's exclusion
from the Committee.
The Uitvoerend Bewind was not willing to accept La Pierre's
recommendation but did demand on June 11 that every member
of the Committe for the Affairs of the Colonies submit a written
statement declaring that they had not had any communication
with Tierce.28
All the members of the Committee for the Affairs of the Colo-
nies, except Coerman, promptly complied with this request.29
Coerman promised to submit a separate statement which he did
on June 15. In it he acknowledged that he had known Tierce
when he lived in Curagao and had been pleased to meet him
again. He respected Tierce for his role in the suppression of the
slave revolt and considered the exile of his friend from the island
an act of injustice. Coerman contended that Tierce most likely
had been deported because he had discovered serious dishonesty
in the execution of the will of a certain Brion. Coerman did deny,
however, that he had divulged anything of substance to Tierce
although he did acknowledge having had conversations with
him. 30
Upon the request of the Uitvoerend Bewind, the Committee
for the Affairs of the Colonies reluctantly expressed its views on
Coerman's behavior. It agreed that he had been guilty of indis-
cretion and added that it had never been too impressed with
Coerman's role on the Committee because of his 'turbulence and
temperamental constitution'.31 Subsequently, the Uitvoerend
Bewind on July 26 expressed its 'serious displeasure' over
Coerman's 'thoughtless temper and imprudence' and urged him
to be more careful in the future.32

More serious were the diplomatic repercussions of the Tierce
affair. Already a few days after Tierce's arrest the Spanish ambas-
sador to the Batavian Republic, Anduago, requested the govern-
ment not to release the prisoner before he had had an opportuni-
ty to interrogate him on the attempted coup d'itat in Caracas.33
While this request, which was repeated in late July, could be
honored, the demands submitted by the French ambassador
SEmonville produced a more serious problem. Already on May 27
Simonville demanded that if Tierce were a French citizen em-
ployed as French consul in Curacao he be promptly released.34
Two weeks later the French ambassador demanded that all deci-
sions against Tierce, who was undoubtedly a French citizen and

JEAN-BAPTISTE TIERCE AND THE BATAVIAN REPUBLIC 7
therefore entitled to the protection of his government, be suspen-
ded. Furthermore, Scmonville demanded that his secretary be
permitted to question the prisoner.35 The .Uitvoerend Bewind
requested La Pierre onJune 12 to advise the foreign minister how
to reply to SEmonville's inquiries and demands. La Pierre denied
that Tierce was a French citizen since he had become a Batavian
citizen because of his service as an officer in the national guard.
Furthermore, although Tierce had once served as French consul,
he was never officially appointed to that function by the French
government. Moreover, his consular duties ended in April 1798
almost one and one-half year before his arrest and expulsion.
Later Tierce served as receveur, but he held that position only at
the fiat of the Batavian officials. Therefore, La Pierre concluded,
Tierce could not under any circumstances appeal for protection of
the French government. Naturally, the request to allow SEmon-
ville's secretary question Tierce could not be honored since such a
concession would violate Dutch sovereignty and do harm to Bata-
vian-French relations.36
The Uitvoerend Bewind accepted La Pierre's advice and on
June 16 instructed Foreign Minister Van der Goes to reply to
SEmonville accordingly.37 The latter was unwilling to accept this
rebuff and reiterated with 'greater force' his previous observations
and demanded Tierce's prompt release. He accused the Batavian
authorities of subterfuges in order to suspend his intervention to
obtain the release of a person who had been victimized by the
enemies of the Batavian government in Curacao where Tierce had
successfully foiled the intrigues of the Orangists. 38
The Batavian government, which was often easily bullied by
the French during this time, stubbornly refused to yield in this
matter, however. It even instructed on August 6, 1800, the am-
bassador to Paris, Rutger Jan Schimmelpenninck, to submit a
memorandum to the French government on the events in Sep-
tember 1799 in Curacao and to inform the authorities of 'the un-
healthiness of the claim to consider J.B. Tierce . a French
citizen.'39
In September 1800 the French government discontinued its de-
mands on behalf of Tierce. Perhaps it felt it could no longer
defend Tierce who had been accused of trying to overthrow the
government of Curacao in 1799 after un unofficial, abortive,
French attack on the island between July and September 1800.
This time the Batavian government registered protests and the
French authorities attempted to apologize.40

G.D. HOMAN

Meanwhile, Tierce and Quast had been in the custody of the
Court of Holland and Zeeland which studied the available evi-
dence to enable them to instigate legal actions against the two
men. However, onJuly 24 the Court resolved that since it could
not find sufficient evidence to prosecute them, the two men
would be released on July 28, 1800.41 The Spanish ambassador
attempted desperately to detain them further while he was awai-
ting for relevant documentary material from Madrid, which
would enable him to interrogate Tierce on the Caracas affair. The
Uitvoerend Bewind honored that request on July 28,42 but the
Court refused to relent much. It emphasized the difficulties of
this case that could not be handled 'in accordance with regular
rules.' However, it could not detain the two men merely on the
basis of 'vague accusations.' There simply was not enough
evidence and no corpus delicti. However, the Court was willing to
keep Tierce until August 1 'in order not to render illusive such
political measures as [the Directors] in their position might deem
necessary.'43
The Court's record on human rights during the period
1798-1804 has not been very impressive. It was especially sensitive
to what it considered abuses of freedom of the press, and in May
1802 gave a rather severe sentence toJ.C. Hespe for publishing
two innocent 'dreams' in the Politieke Blixem. However, the case
against Tierce and Quast was handled with equity, although the
Court played a little game with its reference to 'political measu-
res.' What was meant by that became obvious when the Uitvoe-
rendBewind resolved onJuly 30 to order La Pierre to reincarcerate
Tierce upon his release by the Court for the security of the state
and for the maintenance of good relations with the Republic's
allies. Thus the Court informed La Pierre of the time and place of
Tierce's release on August 1, and on that day the latter found
himself again in the custody of the Agent of Internal Police.44
Tierce remained incarcerated until late October 1800 when he
'escaped.' Most likely, Tierce was allowed to escape in order to rid
the Batavian government of what was becoming an embarrassing
problem. Already in late September Delprat noted in his diary
that the government had resolved to allow Tierce to escape.45
Apparently, it took some effort to let the prisoner out of the cage.
On October 15 La Pierre authorized one of his clerks to move
Tierce from the Gevangenpoort to the Mauritshuis because of the
dampness of his cell. This transfer was effected without difficulty
that same day. However, on October 23 Tierce's brother Emma-

JEAN-BAPTISTE TIERCE AND THE BATAVIAN REPUBLIC 9
nuel, who had been permitted to visit him for several weeks,
requested that his brother be returned to the Gevangenpoort
because his cell was too cold for a person who had lived for more
than 30 years in the tropics. Again La Pierre consented, but
during this transfer the next day Tierce with the assistance of
others broke loose from his guards and disappeared in the dark-
ness of the evening.46

Tierce safely arrived in Paris, but he refused to concede defeat. In
December 1800 he forwarded an eight-page pamphlet47 to the
Batavian government in which he tried to defend and vindicate
himself. He lamented his suffering at the hands of the Orangists
in CuraCao and accused Lauffer of being 'crafty and dissimula-
ting.' He had neglected the defense of the island, Tierce charged,
and refused to listen to him and Kikkert to prepare Curacao for a
possible outside attack. In conclusion, Tierce requested permis-
sion to return to Curacao to attend to his business, his extensive
and complicated administration, and to repair all the damage
Lauffer had caused to his house, warehouse and commerce. Natu-
rally, the Batavian government refused to relent and Tierce recei-
ved no reply.

This was not the end of the Tierce affair, however. On March 18,
1801, reports reached La Pierre that Tierce had had the audacity
to return to the Batavian Republic. Immediately, the Agent asked
the UitvoerendBewindfor permission to arrest and deport him, a
request that was promptly granted.48 Tierce was arrested in Am-
sterdam on March 21 and deported two days later. Why had he
returned to the Batavian Republic?49 Most likely out of sheer
frustration and desperation to obtain a favorable decision from
the Batavian authorities to permit him to return to Curacao. He
might have hoped that his friend Kikkert, who had returned
home, to assist him. But Kikkert had no influence with the
authorities, and to the best of my knowledge, Tierce never retur-
ned to his beloved Curagao.

12. Lauffer to Comite van de Kolonien, Nov. 7, 1799. A.R., ComitE van de
Koloniin, Messages and Enclosures from Curacao, 1796-1802, no. 136. A copy
of this same letter can also be found in A.R., Agent Algemene Politic, Secret
Related Documents, no. 228.

(42).
Continued from N. W.I.G. 50, 1975, p. 62-76, and previous lists since 1947. -
Publications not seen by the compiler of this incomplete bibliography are not
included. The existence of a Summary is indicated by a translation of the title.

Emmer, Pieter Cornelis: Engeland, Nederland, Afiika en de slavenhandel in de
negentiende eeuw. Thesis Leiden 4.X.1974, xi + 146-215 + 44-144 pp. 24 x
15% cm. Summary on p.v-vii: 'the introduction poses the question as to
wether the Dutch did or did not take part in the illegal slave trade of the 19th
century; which international measures were taken to stop the trade in blacks and
to what extent the development of the Dutch slave trade was affected by these
measures.' Part I from Econ. Sociaal-Hist. Jaarboek 36, 1973; II from Jaarboek
37, 1974.

Proceedings of the Fifth International Congress for the study of pre-columbian
cultures of the Lesser Antilles, Antigua, July 22-28, 1973. The Antigua
Archaeological Society, 1974; Ripley P. Bullen ed.

Westlake, Donald E.: Under an English heaven. Being a true recital of the
events leading up to and down from the British invasion of Anguilla on March
19th, 1969, in which nobody was killed but many people were embarrassed'.
Simon and Schuster, New York, 1972, 278 pp. 21 x 13 % cm, 29 figs. on 10
pls. excl. (St. Martin mentioned.)

Abstract Samenvatting ............................... 1
General geological observations .......................... 5
The area of Caracasbaai ................................ 9
Investigations off-shore from Caracasbaai ................... 16
Dating the event ...................................... 25
The probability of a new catastrophic event ................. 29
References ........................................ 32
ABSTRACT
During previous geological fieldwork in Curacao indications were found that
the Caracasbaai, a bay with an open front of about 1 km in width and a maxi-
mum depth of about 250 m, situated along the south-western side of the island,
owes its existence to a submarine slide of a large part of the limestone coast-
range. The evidence was largely based upon geological and geomorphological data
from the vicinity of the Caracasbaai. These data indicated that in sub-recent
time a coastal fragment of about one square kilometer, its top surface at least 45
m above sea level and its basis along the seaward side about 250 m below sea
level, has disappeared in south-south-western direction, sliding down the rather
steep submarine slope separating the island from the deep trench to the south-
west.
In 1970 echosounding profiles and off-shore sampling fully confirmed the ob-
servations made on land. A huge scar with an almost flat bottom, 1000 m in
width and excavated a 150 m below the surrounding level of the sea-bottom, is
present over a distance of several km in front of the Caracasbaai. At a distance
of about 5 km and a depth of about 800 m the broad scar gradually gets a more
south-south-eastern direction and merges into a V-shaped canyon.
There are indications that at this depth of about 800 m the block, down to there
acting as a single unit, broke into several smaller fragments.
The volume of the limestone block that disappeared from the Curaao coast-
line is estimated at 150 million m3 and the volume of unconsolidated globigeri-
na-oozes, set in motion by the sliding block, amounted to 700 million m3.
The sliding event was ofa sudden character and the effects on land must have
been of a catastrophic nature.
Although the limestones of the Seroe Mansinga. a mountain immediately
north-west of the Caracasbaai. are in a less stable position than limestones else-
where in the coast-ranges of the island, this risk of a new catastrophic event is
almost negligible, estimated at one chance in several millions of years.

ACKNOWLEDGEMENTS
The authors wish to express their sincere gratitude to The Netherlands Organi-
zation for the Advancement of Pure Research, Z.W.O. and The Royal Nether-
lands Navy.
The authors are also greatly indebted to the Commander, Officers and Crew of
H.NI.M.S. 'Luymes' for their personal assistance and close cooperation during
the investigations.

CARACASBAAI: A SUBMARINE SLIDE

GENERAL GEOLOGICAL OBSERVATIONS

The main axes of the three islands Aruba, Curacao and Bonaire,
arranged en echelon along the northern coast of the South-Ame-
rican mainland, are each directed from north-west to south-east
and a constant due eastern trade wind renders the straight and
rough north-eastern coasts of the islands inaccessible for shipping.
The south-western, leeward shores on the contrary possess excel-
lent natural harbours, partly in the form of hand-shaped inland
bays, drowned valley systems situated land inward from the lime-
stone coast-ranges, and partly consisting of open bays or concave
parts of the coast line, offering sheltered position even for large,
heavy-draught ships.
The coral limestones in the three islands are deposited uncon-
formably on thick series of a folded Cretaceous and Danian
eugeosynclinal sequence, mainly volcanic rocks, silica-rich sedi-
ments and turbidites (Curacao; Beets, 1972), on folded, meta-
morphic volcanics and sediments with intrusions of gabbros and
diorite batholiths (Aruba; Westermann, 1932, 1949) or on fol-
ded series of volcanics and calcareous or silica-rich sediments with
pophyritic intrusions (Bonaire; Pi/pers, 1933). In places lenses of
Paleogene sediments, less strongly folded, occur between the
younger reef limestones and the older, mainly volcanic forma-
tions.
The Neogene and Quaternary coral limestones are mainly
found in the peripheric zone of the islands. They occur to a maxi-
mum height of about 200 m above sea level and are developed as
relatively thin deposits, showing a strong resistance against
subaerial erosion. The underlying, mainly volcanic and non-cal-
careous rocks are much less resistant against subaerial erosion and
are exposed in the central parts of the islands.
The coral limestones of the coast-ranges may be roughly divided
into two different types: one type developed mainly along the
windward sides, the other type occurring nearly exclusively along
the leeward coasts.

58 P.H. DE BUISONJE ANDJ.I.S. ZONNEVELD
The limestone coast-ranges along the nort-eastern, windward
sides consist of series of marine accumulation terraces, separated
from each other by elevated, marine cliffs. In Curacao four terra-
ces may be distinguished, step-wise descending from the oldest,
highest terrace with a top level between 150 and 90 m to the
youngest Lower Terrace, situated only 10 m above sea level. These
terraces were formed by reefs growing upward from the sea-bot-
tom and contain reef corals in position of growth as well as
lagoonal sediments deposited between these reefs and the shore.
The terraces were deposited during Quaternary periods of slow re-
gression (the upper two terraces) or of slow transgression (the two
lower terraces).
In the hinterland strong degradation took place and valley
systems were carved out, especially during the (glacial) periods
with low sea levels (much lower than 20 to 25 m below the present
one).
In the final stage of the Lower Terrace transgression a sea level
was reached, leaving traces that now are found up to 10 m above
the present water line. The valley systems in the hinterland were
drowned and even in these hand-shaped drowned-valley-bays the
circumstances were favourable for reef growth.
After this final stage the sea level lowered and the upper part of
the Lower Terrace sediments came above sea but the low level
prior to the Lower Terrace transgression was never reached and
large parts of the hand shaped valley systems are still filled with
sea-water.
Considered as a whole, the series of terraces indicates that
Quaternary eustatic sea level changes were superimposed on a
slow, vertical and upward movement, not only of the island of
Curacao, but also of the islands Aruba and Bonaire where terraces
of identical nature occur at the same levels as in Curacao.
The limestones of the coast-ranges along the south-western si-
des of the islands, although of completely different faces, nature
of deposition and partly also older (Neogene), show the same ef-
fects of a slow, vertical upward movement of the islands. These
leeward coast-ranges consist of erosional remnants of emerged
reef talud deposits. They never contain reef corals in position of
growth but only show the detritus of such hermatypic reefs, often
mixed with pelagic organisms.
They show a chaotic arrangement of the reef detritus, a bed-
ding that may be followed in the direction of the strike only over
short distances, and nearly everywhere have a seaward dip of the

CARACASBAAI: A SUBMARINE SLIDE 59
stratification. These dips are mostly between 100 and 250, but
sometimes up to 320, the maximum angle of repose of unconsoli-
dated detritus.
The limestones of the leeward sides of the islands are deposited
from slumping reef detritus. Reef growth near sea level along the
shore continuously brought masses of unconsolidated material in
an unstable position and ever and again submarine slumps occur-
red, adding new strata to the reef talud deposits far below sea le-
vel (Zonneveld, 1960; de Buisonji, 1974). Especially in the
younger parts the deposits contain pebbles derived from the non-
calcareous older formations. From paleontological and paleoeco-
logical data it is concluded that the island has been rising since
late Miocene of Pliocene times (de Buisonji, 1974).
The Quaternary eustatic sea level changes that are (together
with the vertical, upward movement of the islands) the main cau-
ses for the terrace development along the windward shores, left
only minor effects in the emerging reef talud deposits along the
leeward shores. Here in places erosional terraces were truncated at
levels identical with those of the accumulation terraces from the
windward coasts. Only the two lowest terraces have here a partly
depositional nature (Fig. 1).

THE AREA OF CARACASBAAI

Main features of the Caracasbaai area are the relatively high ero-
sional remnants of the limestone coast-range, such as the Seroe
Mansinga (47 m) to the north-west and the Kabrietenberg (80
m), Seroe Boca (81 m) and the Tafelberg Santa Barbara (196 m)
to the south-east of the Caracasbaai, dominating over the low,
gently undulating landscape landinward and the inland bay of
Spaanse Water with its natural entrance between the Kabrieten-
berg and Seroe Boca (Fig. 2).
The limestone coast-range south-east of the Caracasbaai shows
a completely normal development: flat-iron shaped erosional
remnants of emerged reef talud deposits with their seaward dip-
ping top surfaces and basal planes and a slightly steeper dip of the

60 P.H. DE BUISONJE AND J.I.S. ZONNEVELD
stratification. Along the lower, seaward side of the Tafelberg San-
ta Barbara the effects of the slow regressions and transgressions,
main causes for the four terrace depositions in the windward
coast-range, are here, along the leeward side of the island,
discernible as well: two erosional surfaces, truncated at 100-110
m and about 60 m from the 200 seaward dipping reef taluds and
two depositional terraces at 20-45 m and 10 m, the Middle and
Lower Terrace respectively.
In the Seroe Boca and the Kabrietenberg the Middle Terrace is
largely of an erosional nature and in the Seroe Mansinga Middle
Terrace deposits are completely lacking. Lower Terrace deposits
are completely absent along the Caracasbaai itself and from the
south-western side of Seroe Mansinga.
The triangular (flat-iron) shape of the erosional remnants of
the coast-range is caused by the strong subaerial erosion, at-
tacking the dipping limestone beds from the land-inward side
and especially from erosional gullies draining the interior. The
volcanics are much less resistant and therefore show strongly de-
graded forms in the hinterland.
The strong difference in subaerial erosion resistance between
volcanics and limestones is also demonstrated by the presence of
the inland bay of Spaanse Water. This drowned valley system
with its small peninsulas all directed towards the natural outlet to
open sea, shows the place where several rivulets (so-called
'rooien') came together and in combined effort remained in
connection with open sea throughout late-Neogene and Quater-
nary times.
During the high sea level at the end of the transgressive Lower
Terrace development the slightly meandering natural outlet of
Spaanse Water, situated between the Kabrietenberg and Seroe
Boca was the only connection with the open sea and possessed a
depth of about 25-30 metres. In the inland bay reef growth occur-
red along the tips of peninsulas and small inlands close to the
natural outlet of the bay (Fig. 2).
The Caracasbaai itself with its open front of 1 km in width and
its maximum depth of 250 m is not a 'normal' feature in the
coastal landscape. There are several reasons for supposing that it
was formed by a giant slide, during which a huge block of the
limestone coast-range slid down into the adjacent sea.
The above-mentioned distribution of the Lower Terrace develop-
ment inside the Spaanse Water offered an important clue for the
presumption that the Caracasbaai was still occupied by limestones

CARACASBAAI: A SUBMARINE SLIDE

of the leeward coast-range even in rather recent times. The topo-
graphic situation indicates that at the end of the Lower Terrace
development (dated as less than 31.300 500 yrs. B.P.; see de
Buisonji, 1974) no open connection existed between the north-
western part of the Spaanse Water and the open sea, other than
via the natural connection between the Kabrietenberg and Seroe
Boca; should the Caracasbaai have been present in that time,
Lower Terrace development surely would have been concentrated
in this north-western part of the Spaanse Water and in the Cara-
casbaai itself.
Is this connection it is worth mentioning that according to Simons (1868, p.
36) the dam, connecting the Kabrietenberg and Fort Beekenburg with the main
island of Curaqao near Brakke Put was originally an artificial one, made as a
defensive work against enemy ships attacking Curagao. The name Caracasbaai
comes fromt the Dutch word 'kraak' or English carrackk', crackc' or 'carac',
rather large ships used during the 16th and 17th century, mainly by the
Spaniards and Portuguese. It was much easier to enter the wide Caracasbaai than
to enter the meandering natural outlet of the Spaanse Water between the Ka-
brietenberg and Seroe Boca, especially with larger sailing-vessels.

62 P.H. DE BUISONJf AND J.I.S. ZONNEVELD
A second argument for a sub-recent development of the Caracas-
baai may be found in the straight cliff, bordering the north-
western side of the bay and possessing an almost vertical submari-
ne continuation to a depth of about -250 m. This vertical cliff, or
properly speaking fault-escarpment, over a horizontal distance of
1000 metres perpendicular to the main coast line of the island,
cuts off the limestone coast-range over its entire width (Fig. 3-5).
From soundings in the Caracasbaai it was already known in 1956
that the maximum depth of -250 m is reached close to the sea-
ward limit of the escarpment near Lijhoek. The steep submarine
gradient of over 700 indicated that here, in the lower parts of the
escarpment, only hard rocks are exposed because the maximum
angle of repose of unconsolidated material never exceeds 320. In
its turn, this steep, almost vertical continuation to such a depth
excludes the possibility that the escarpment originated from nor-
mal marine cliff development or from terrestrial erosion, for any
indication of previous sea levels below the -25 m depth line are
absent in the bays from Curacao.
In another way too, the straight escarpment near the Caracas-
baai shows effects that are not normal in the leeward limestone
coast-range. In Fig. 5 these effects are visible: the dips of the stra-
tification are mostly land inward and several faults dissect the
limestones. These steep faults are inclined seawards and near the
land-inward limit of the escarpment a saucer-shaped limestone
deposit cuts off older limestones.
The limestone blocks between the steep faults and also the sau-
cer-shaped deposit are all truncated by the slightly seaward dip-
ping top surface, reaching a maximum height of 47 m above sea
level.
Now all the reef talud deposits elsewhere in the islands have a
seaward dip of the stratification; Seroe Mansinga is the only
exception.
Perhaps this situation indicates that the original submarine reef
talud deposits of the Seroe Mansinga including those that were
present in the place now occupied by the Caracasbaai might
have been involved in a minor submarine slide after which they
got a new and more stable position with land-inward directed
dips and were dissected by steep faults, long before they emer-
ged. Later they were truncated at the time that elsewhere the
Middle Terrace (20-45 m) was deposited (de Buisonji, 1974).
Only after the final stage in the Lower Terrace development the
south-eastern part of the temporarily stable mass of Seroe Man-

CARACASBAAI: A SUBMARINE SLIDE

singa-Caracasbaai was again involved in a movement: the Cara-
casbaai development.

A third argument for the conclusion that the Caracasbaai is the
result of a sub-recent slide, may be seen in the surroundings of
Fort Beekenburg at the eastern side of the Caracasbaai. The
fortress was built on top of a huge limestone block lying in the
shore-line and protruding about 17 m above sea level. The block
apparently is part of a limestone slab, dipping in N and NE direc-
tions and broken into a number of more or less square blocks that
are now separated by steep vertical clefts, each several metres
wide. About 200 m N of Fort Beekenburg a much more irregular
accumulation of large blocks gives the impression that some giant
dices have been thrown around (Fig. 3 and 6).
In size the blocks resemble those found scattered elsewhere in
the islands in the foot hills along the land inward erosion escarp-
ments of the limestone coast-ranges. But here, near Fort Beeken-
burg they are found in a greater number. They are clearly derived
from a larger continuous limestone cover, but the cover itself is
lacking from the scenery.
In another way too the blocks give some information. Some of
them, especially the larger ones, have a strong development of a
typical karst surface on top, exactly in the same mature state of
development as old karst surfaces elsewhere in the higher parts of
the limestone coast-range. Blocks in a tumbled position show
their original karst surface in one of the side-walls (Fig. 7-8), but
on their present top surface not the slightest trace of newly for-
med karst is found. This is again an indication that the blocks got
their present position only in sub-recent times.

A fourth argument for a sub-recent and sudden development of
the Caracasbaai is found in the same area. The Lower Terrace
deposits, encircling almost completely the islands of Curacao and
Bonaire, are lacking completely even from otherwise favourable
spots along the Caracasbaai and from Seroc Mansinga. Any indi-
cation of the former sea level at + 10 m, especially the develop-
ment of a solution notch (de Buisonji & Zonneveld, 1960; de
Buisonji, 1974), is not only absent in the escarpment along the
north-western side of the Caracasbaai, but is also lacking in the
Ford Beekenburg blocks, again pointing to a young (post Lower

Terrace) date for the Caracasbaai slide.

^ P.H. DE BUISONJI AND J.I.S. ZONNEVELD

During the international program of the Cooperative Investi-
gation in the Caribbean and Adjacent Regions (CICAR), from
1970 to the end of 1972, the hydrographic vessel 'H. N1. M. S.
Luymes' of the Royal Netherlands Navy was stationed in the Ca-
ribbean, enabling detailed scientific research in the areas around
the Netherlands Antilles and north of Surinam, areas previously
only superficially known. One of us (de Buisonjej had the op-
portunity to take part in the investigations in the Curacao area.

The 'Luymes' was equipped with a Kelvin Hughes Precision Depth Recorder
(PDR). type MS 38 F/M Mk 1, a smaller echosounder, type MS 36 M/A Mk 1
and on board of one of the motor launches an echosounder, type MS 26 F was
installed. All instruments were calibrated at 1500 m/sec and the two instru-
ments on the 'Luymes' corrected by 4 m for the draught.
With a specially designed winch, steel wire and a bottom sampler of the Van
Veen type or of the steel pipe piston corer type it was possible to take samples
under simultaneous registration of echosounding profiles on the PDR.
In the day-time a continuous position fixation was enabled by a DECCA-
system and two DECCA-stations in the islands, later on they were moved to the
shore of the South-American mainland. During the night, owing to nocturnal
fluctuations in the wave-length of the DECCA-system, only visual bearings on
landmarks in the islands, together with RADAR-distances could be used for po-
sition fixation. For this reason the echosounding registrations in large runs,
mainly more or less perpendicular to the coast lines of the islands, were made
exclusively during the day-time. Sampling of the sea-bottom was largely done at
night and in places where points of special interest showed in the previously
made echosounding profiles.
During the sampling operations so-called 'drifting stations' were used. The
'Luymes' then was left drifting (with the speed zero or with stopped engines) in
a westward direction (course 270) by the constant, mostly due eastern trade-
wind.
Echosounding profiles, taken when the ship with a normal speed of about 12
knots and in eastward direction (course 090) headed for a sampling station, gave
information beforehand over the stretch of the sea-bottom that would be passed
afterwards during the drifting sampling station. From such additional profiles
the exact moment to let run out the steel wire with the sampling apparatus
could be chosen and during the sampling a reversed echosounding profile was
obtained, this time with an almost equal vertical and horizontal scale, due to the
slow drifting speed of about one nautical mile an hour.

CARACASBAAI: A SUBMARINE SLIDE 65
Finally attention must be drawn to the steep-sided,
longitudinal diabase hill, present immediately north-east of Fort
Beekenburg (see Fig. 3). The top of this hill is about 17 m above
sea level and the north-eastern side steeply descends to the water
of the inland bay of Spaanse Water. Diabase hills of this height
and with such steep sides do not occur elsewhere around the
Spaanse Water and the steep-sided hill near Fort Beekenburg is
considered to represent an erosional remnant of the steep foot
slope behind the land-inward side of the limestone cover that up
to a sub-recent date occupied the place of the present-day Cara-
casbaai.

All these observations support the assumption that after the final
stage in the Lower Terrace development a part of the coast-range
slumped down in a direction perpendicular to the coast, in such a
way that an open connection was formed between the Spaanse
Water and the sea west of the Kabrietenberg.
Only in the eastern part of the Caracasbaai area a small rem-
nant of basal limestones was conserved and the underlying volca-
nics did not take part in the movement. Immediately south-west
of the line where the basal slump plane must intersect the surface,
two slabs of limestone, each broken into large blocks, are left dip-
ping in directions that are not the original ones. A chaos of
tumbled limestone blocks is lying upon what might be the rem-
nant of the footslope of a former limestone escarpment.
The echo-soundings in the Caracasbaai itself give the impres-
sion (see Fig. 12) that south-west of Fort Beekenburg another
rockmass was stuck in a somewhat lower position, its top about
50-30 m below sea level.
Later a shingle beach and an artificial dam were built in the
shallow water between the newly formed Caracasbaai and the
Spaanse Water.

INVESTIGATIONS OFF-SHORE FROM CARACASBAAI

The final evidence for the conclusion that this bay owes its
existence to a catastrophic slide is given by the results of the off-
shore investigations.

Fig. 3. Vertical aerial view of the Caracasbaai, Curafao. Left the Seroe Man-
singa, consisting of elevated Neogene reef talud limestones, with an almost ver-
tical fault escarpment separated from the Caracasbaai which reaches a depth of
over 250 m near the centre of the photograph. In the upper right corner two
broken slabs of reef talud limestone are visible, remnants of the huge limestone
deposit that occupied the place of the present Caracasbaai up to sub-recent
time. Fort Beekenburg (arrow), a 17th century fortification, has been built on
the southernmost slab which slid down and slightly rotated. East of Ford Bee-
kenburg a chaos of tumbled limestone blocks. Note the steep-sided, longi-
tudinal diabase hill, running north-south near the tanks, between the two
roads, north-east of Ford Bcckenburg.

Fig. 4. Seroe Mansinga, oblique aerial view (1960). The Neogene reef talud limestones of the Seroe Mansinga, left, are cut off over their
total width by a straight and almost vertical fault escarpment. In the right upper corner an artificial dam connects the diabase mainland
in the background with the island on which some oil reservoirs are visible. Lower Terrace deposits, almost completely enuirling the
island of Curacao, are lacking in these surroundings.

Fig. 5. Seroe Mansinga, horizontal view (1960). Strong disturbances of the originally seaward dipping talud deposits, afterwards
almost horizontally truncated in Middle Terrace time, seem to indicate thad the deposits of Scroe Mansinga were involved already in n ear-
lier sliding movement. Only in sub-recent time the disappearance of a huge limestone block exposed the straight, about 1000 m long
fault escarpment in this photograph.

Fig. 6. Caracashaai, seen from the Kabrietenberg (1960). In the foreground the very shallow water of the Spaanse Water, separated from
the extremely deep water of the Caracasbaai by a series of scattered limestone blocks. These blocks are vestiges of the huge reef talud deposit,
formerly present between the Kabrietenberg and Seroe Mansinga in the background. Fort Beekenburg (arrow), is built on one of the
scattered limestone blocks, lying on the present shore.

Fig. 7. Some of the large limestone blocks in the immediate vicinity of Fort
Beekenburg (1956). Note the mature karst surface, now in an abnormal verti-
cal position in the block on the left side. Dripstone striae, originally deposit-
ed in a vertical cleft, are now in a horizontal position. A new karst surface
has not yet developed on the present top surface of this block. Note also the
absence of a horizontal solution notch in the blocks, elsewhere an accompanying
effect at the + 10 m level during the final stage in the Lower Terrace develop-
ment (the level of the road is only 2 m above sea level).

Fig. 8. Detail of the preceding photograph (1956). The mature karst surface
with consolidated, reddish brown weathering products still present in the origi-
nally vertical solution depressions, together with complete absence of newly
developed dripstone, indicates that the whole limestone block got its present
position only sub-recently.

Fig. 9. Echo sounding profile during deep sea sampling (C13-006). During
this sampling the ship's velocity was reduced to zero, only influenced by the al-
most due easterly trade wind. The drifting speed was about one nautical mile
per hour (1800 m/h). As a result there is almost no vertical exaggeration in scale.
The vertical line to the right indicates the start of the sampling operation, using
a steel pipe piston corer. The faint, oblique line indicated with three small
arrows, seems to give a picture of the steel wire when the corer hit the bottom.
The oblique line, however, is a result of the echo sounder, continuously giving
reflexes from the massive piston corer during its descent along line C13-006,
while the ship was continually drifting to the west. The profile is nearly an
exact copy of the vertically exaggerated profile L-L' from Fig. 11.

CARACASBAAI: A SUBMARINE SLIDE 75
During the first night of CICAR-cruise 13, June 11th 1970, off-
shore from the Caracasbaai, without any detailed information
on the sea-bottom morphology, a special procedure was followed.
In order to obtain information on the sediments present in front
of the Caracasbaai, a series of six samples was taken with the steel
pipe piston corer. The sampling stations were situated in a semi-
circle around the Caracasbaai and at depths between 740 m and
880 m.
From this series five samples showed the presence of globigeri-
na-oozes. The thickness of penetration of the piston corer in these
unconsolidated oozes was between 24 cm and 124 cm, measured
from the length of the recovered cores. In all five cases there was
smear on the outside of the corer, in some cases over greater
length than the core itself, indicating that the core was only part-
ly recovered.
As was shown during sampling later on in CICAR-cruise 13,
and will be discussed in a future paper, the globigerina-oozes are
the normal sediments below the 200 m depth line around the
islands and in exceptional cases, where recent or sub-recent slides
had occurred, detritus of hermatypic reefs was found at larger
depths, in some cases even below the 1000 m depth line. In such
exceptional cases the detrital reef sediments are always unconsoli-
dated.
But from the six samples taken in front of the Caracasbaai one
was of completely different nature. It consisted of a few hardrock-
fragments of a conglomeratic limestone containing diabase
pebbles and hermatypic coral detritus, and further some broken
recent deep sea corals, fragments of recent deep sea silica sponges
and some recent globigerinids and other small pelagic foraminife-
ra. The piston corer did not show any outside smear and the sharp
cutting edge of the steel pipe was badly damaged, indicating that
hard rock was hit by the corer.
The conglomeratic limestone from this sixth sample (CICAR
13-006; position 12-00.6 N, 68-52.3 W; depth 880 m) is identi-
cal with the limestones exposed in the Seroe Mansinga along the
north-western side of the Caracasbaai. Here consolidated detritic
reef talud limestones occur, containing well-rounded diabase
pebbles, derived from the hinterland, mixed with rounded frag-
ments of hermatypic coral colonies, algae and other lime-secre-
ting neritic organisms.
From the echosounding profiles taken during sampling it was
clear that sample CICAR 13-006 was derived from the deepest

B B

Fig. 10. Series offourecho sounding profiles. The profiles are taken with
the aid of a Kelvin Hughes precision depth recorder, type MS 38 F/M Mk 1. The
positions of the profiles are given in Fig. 12. Profiles are from the upper part
of the broad scar caused by the huge limestone block of the Caracasbaai, sliding
down-slope in unconsolidated globigerina-oozes ot the island talud. The
width of the scar is about 1 km, indicated with a black line; depths are in
metres. Note the extremely flat bottom of the scar profile D-D' and F-F' and
the relatively high western side of the scar in profile B-B'. As a result of the ships
velocity of about 10 knots, the vertical exaRneration is about 10 times the hori-
zontal scale.

78 P.H. DE BUISONJE AND J.I.S. ZONNEVELD
point in a submarine depression with a V-shaped cross-section
(Fig. 9).
Only the next day, when the sea-bottom morphology off-shore
from the Caracasbaai became more accurately known from a large
series of echosounding profiles (Fig. 10-12), it became evident
how extremely lucky this sixth 'shot in the dark' had been.
Sample CICAR 13-006 had exactly hit the deepest point of a
V-shaped erosional canyon, the continuation of a large, broad
scar present in the sea-bottom in front of the Caracasbaai.
In Fig. 12 the runs of the echosounding profiles are given and
part of the constructed depth lines are indicated. The figure
shows that over a distance of about 5 km from the coast of Cura-
cao, exactly in front of the Caracasbaai, a huge scar is excavated
from the sea-bottom. This scar has in its upper course an extreme-
ly flat bottom and a width of 1000 m. The scar is situated about
150 m below the surrounding level of the sea-bottom and has
steep sides.
At a distance of about 2 km from the Caracasbaai the direction
of the scar slightly alters from N 220 E in its upper course to N
195 E in its lower part. At the same point the eastern side of the
scar diminishes in height.
Between 4 and 5 km from the Caracasbaai the steep western
side of the broad scar also diminishes in steepness and moreover
clearly shows a gradual change in direction, more to the south-
south-east.
At about 6 km from the Caracasbaai the sides of the broad scar
merge into the sides of a V-shaped submarine canyon, continuing
in a direction N 150 E. Sample CICAR 13-006 was situated exact-
ly in the central axis of this V-shaped canyon.

From the shape of the cross-section of the scar in the sea-bot-
tom between Lijhoek and a point situated about 4 km to the
south-south-west it is concluded that up to this point the sliding
limestone mass from the Caracasbaai acted as one single unit,
possibly of an asymmetrical shape. A slide, consisting of several
individual smaller quantities or several smaller slides separated by
time intervals, would never have caused a scar with such a flat
bottom but would probably have resulted in a series of V-shaped
canyons already close to the shore. The flat bottom of the scar in
its upper part, together with its width being identical with the
width of the open front of the Caracasbaai, are arguments for the
idea that the sliding Caracasbaai limestone block was a very large

CARACASBAAI: A SUBMARINE SLIDE 79
one. This is in close accordance with the arguments based on ter-
restrial observations.
That the sliding block possessed an asymmetrical shape is not
only indicated by the shape of the Caracasbaai itself, having a
straight and steep, nearly vertical boundary along the north-
western side and a less steep, more gently curved eastern side
(where at least three slumped limestone slabs were stuck), but is
also indicated by fact that the scar in the sea-bottom shows a
steep, clearly defined western side and a less pronounced eastern
side.
It seems probable that the asymmetrical shape and hence an
excentric gravitational mass centre, situated in the western half of
the sliding block, together with an unequal distribution of drag
forces excerted on the block when excavating the flat bottomed
scar, also caused a rotation in a clock-wise sense. Such a clock-wise
rotation is not only considered the main cause for the change in
direction of the broad scar but is also held responsible for the scat-
tering of the block into several smaller fragments, somewhere
between 4 and 6 km from the Caracasbaai. Breaking up of the
block was moreover facilitated by steep vertical faults, already
present in the Caracasbaai-block as a result of the earlier move-
ments of which the limestones in the Seroe Mansinga still bear
testimony.
That some of the smaller block fragments remained in the cen-
tral axis of the V-shaped canyon is conceivable and from the fact
that the piston corer hit one of these fragments, follows again an
argument in favour of a sub-recent date for the Caracasbaai slide.
For if the slide had occurred long ago, the fragments of the origi-
nal Caracasbaai-block, even when they had dimensions such as
those exposed along the shore near Fort Beekenburg, would have
been covered by a thick layer of globigerina-ooze, deposited after-
wards from normal pelagic sedimentation.
In view of the possibility that the broad scar in the sea-bottom
left by the sliding block of the Caracasbaai is a stretch where
conglomeratic limestones are stripped of a covering layer of un-
consolidated globigerina-oozes, some 150 m in thickness in that
case, three additional samples were taken. CICAR 13-016 and
CICAR 13-017 taken from the broad scar at depths of 602 and
724 m respectively, both indicated the presence of globerina-
oozes only. The third sample CICAR 13-018, depth 780 m, taken
from the western side of the broad scar but outside the scar
proper, again consisted of unconsolidated globigerina-ooze.

80

J J'

Fig. 11. Seriesofthree echo sounding profiles. Continuation of the series on
Fig. 10. In profile H-H' the height of the western side is still about 100 metres,
but in the next profile this height diminishes. In profile L-L' the shape of the
cross section, originally with a flat bottom and steep sides, is changed into a
V-shaped erosional canyon. The deepest part of this canyon, here shown with a
vertical exaggeration of 10 : 1, is almost identical with the profile from Fig. 9,
taken during sampling of C13-006.

84 P.H. DE BUISONJE AND J.I.S. ZONNEVELD
We assume that the block slid down the slope into a pre-
existing gully system and that the smaller fragments, after scatte-
ring of the block, used and perhaps also deepened a minor branch
that was present in the Caracasbaai area (Fig. 13). As to the di-
mensions of the sliding block it can be stated that the rock mass,
now lacking from the coast-range had an upper surface of about
one square km and a thickness of approximately 45 m along the
inward side and a thickness of about 250 m along the shore.
The amount of rock involved (mostly limestone with some
volcanic basement) is estimated at 150 million m3, representing a
weight of some 375 million tons. The amount of unconsolidated
off-shore sediments, set in motion by the sliding block when it
carved out the scar, was a multiple of this amount and may be
estimated at 700 million m3 with a weight of some 1,400 million
tons.
Perhaps the greater part of it has been (re-)deposited in the fan
like form south ofsamplepoint C 13-018 between 750 and 900 m
depth (Fig. 13).
When taking into consideration the sudden character of the
event, the effects on land must have been of a catastrophic natu-
re. It is most probable that during the slide a withdrawal of sea-
water took place, closely afterwards followed by a huge wave, a
tsunami that swept over south-eastern Curaqao and probably
inundated a large part of the hinterland. It is possible that this
huge wave was responsible for the disappearance of the Lower
Terrace between the Caracasbaai and Cornelisbaai to the north-
west, this stretch of the coast over a length of about 3 km lying
exactly in a landward direction from the lower, V-shaped erosio-
nalcanyon.

DATING THE EVENT

From three radiometrically 14C dated shell samples of the Lower
Terrace limestones, the youngest has an age of 31,300 500 yrs.
B.P. (de Buisonji, 1974). The emergence of the Lower Terrace
took place only after this date. Together with the observation that
any dissolving action or formation of notches at the + 10 m level
(normal effects in cliffs or limestone blocks during the final phase
in the Lower Terrace development elsewhere) is lacking from
limestones exposed near the Caracasbaai and that moreover newly

CARACASBAAI: A SUBMARINE SLIDE 85

formed karst surfaces are lacking in the tumbled blocks near Fort
Beekenburg, the sliding event may even be dated much less
remote in time, for instance within the last 10,000 years.
Accepting such a recent date for the event, we arrive at the pos-
sibility that the earliest Indians in Curacao, dated at a maximum
age of about 7,000 yrs. B.P. (Du Ry, 1960; van Heekeren, 1960,
1963), may have been witnesses of the catastrophe.

In this connection it is worth-while to mention two folk-tales that may have a
bearing on the case.
The first one is of Indian origin and is told in the South-American mainland
(pers. comm. Ds.J. Mietes). It holds the following story:
'In a remote time groups of violent and combative Indians, coming from
more northern dwelling-places, settled along the northern coast of the South-
American mainland, killed the inhabitants or chased these more peacefull-min-
dcd Indians into the more inland mountainous regions. From this time on con-
stant fights and quarrels with the dangerous immigrants took place and at last
enraged the Indians in the mountains to such an extent that they called a
meeting of their chiefs, a meeting in which the oldest chief was asked to do
something to prevent or to stop the continuous troubles with the new-comers.
- Now the Indians from the mountains were really peaceful people! So their
oldest chief nodded to his friends, took his sharp and long knife, saddled his ce-
lestial riding horse (sic!) and disappeared into the sky in a northern direction,
not in order to kill his enemies but only to draw with his knife a long and deep
furrow between the mountainous region and the coastal lowlands. And what
happened? An enormous landslide took place, separating the coastal area with
the inhospitable immigrants from our friendly people in the mountains. You
do not believe this story? Well, the results of this occurrence are still visible from
our mainland. Go to the coast and look to the north. You will still see the results
of this landslide: the Caribbean islands, each with its surface still dipping in the
direction from where this slide started!'

Although this story is in sharp contrast with the results of geological investiga-
tions in the islands of Curagao, Aruba and Bonaire it has always struck the pre-
sent authors, not only because it contains some correct statements in an anthro-
pological sense and gives expression of a sharp vision on the effects of landslides
in general, but especially because it mentions the possibility of a sliding event in
which a coastal part be it of smaller size than the whole island of Curacao -
disappeared into the ocean.

The second folk-tale is very popular in the Netherlands Antilles. It contains a
more ore less menacing warning to the listener:
'You know our island has the shape of a mushroom. Surely, it has a rather
large surface, but below sea-level it only has a small stalk. So never go with too
many friends to one side of the island for then we all are in danger that the stalk
will break and the whole island will vanish into the deep ocean around!'

86 P.H. DE BUISONJE AND J.l.S. ZONNEVELD
The fear for such a catastrophe was mostly concealed by putting the story in an
interrogative sentence. Even in a radio interview the question 'Is this story true?'
was put to us.
One could suppose that Palaco-Indians, living several thousands of years ago
in Curagao actually witnessed the Caracasbaai slide and that this event lived on
in the folk-tale. But it is more probable that the background of the story is as
follows:
Limestones, whether exposed in marine cliffs or as blocks, broken from cliffs
and surrounded with sea-water, in tropical or subtropical areas often get a deep,
horizontal solution notch, exactly at mean sea-level, with an overhanging rim.
When looking at such a block or coast we immediately compare it with a 'mush-
room' and why should such a mushroom-shape not be present in our limestone-
island as a whole? It is significant that the same folk-tale also exists in areas with
coral islands in Indonesia!

THE PROBABILITY OF NEW CATASTROPHIC EVENT

It can be stated that slides of a size as observed near the Caracas-
baai are very rare occurrences. Over large stretches the coast-
ranges are almost continuously developed and only show gaps,
where erosional products from the hinterland are transported via
normal, originally fluvial breaks to the open sea.
During extensive studies on reef talud limestones exposed
elsewhere in the islands of Curacao, Aruba and Bonaire, only two
or three other examples were observed in which limestone hard-
rock masses were involved in submarine slides. In all other cases
only slides of unconsolidated reef materials were observed,
indicating that normally only the outer parts of reefs are involved
in the slide, leaving the coast proper unaffected.
Two cases of sliding hard-rock, probably derived from an expo-
sed position, above sea-level, are situated in Curacao.
The first was observed in the seaward dipping reef talud depo-
sits of late-Neogene age found near Blauwbaai where blocks of a
detrital reef-limestone occurred in their turn as detritus among
the chaotic elements in an otherwise normal reef talud deposit.
The date of this event, in which probably limestones from above
sea-level were involved in the slide, can be placed in late-Neogene
time, at least several millions of years ago.
The second case is found in the Veerisberg. This flat-iron
shaped erosional remnant of the coast-range near Piscaderabaai is
dissected into two parts, separated by a nearly vertical fault, per-
pendicular to the coast line, running from the top to the lower,

CARACASBAAI: A SUBMARINE SLIDE 87
seaward side of the mountain. The two parts are of unequal thick-
ness, have different basal levels and different top levels. There are
indications that the fault between the two blocks became gra-
dually wider during differential, submarine movement of the two
blocks. The date of this sliding differential movement can be
placed as far back in time as at least several hunderd thousands of
years, possibly even millions of years ago.
Perhaps the queer, semi-circular Lower Terrace development in
the Karpata area (Bonaire) is also the result of a niche left by a
slide. It has partly been filled up by Lower Terrace deposits and
must therefore have been formed more than 30,000 years B.P.
Summarizing, it can be stated that a catastrophic slide of the
size as depicted for the Caracasbaai, occurs with a probability of
roughly one in several hundred thousands or even millions of
years, a probability far below the risks for instance on a large
landslide or an explosive volcanic eruption.
To the rule that Curacao and the other two islands are
geologically safe and 'firm as a rock' only one exception must be
made. The limestones exposed in the Seroe Mansinga, as discus-
sed above, most probably are of exactly the same nature as those
involved in the Caracasbaai slide and are still in a relatively
unstable position.
The presence of several steep seaward dipping faults in the
limestones of Seroe Mansinga, the knowledge that an abnormal
depth of over 200 m is reached within 150 m from Lijhoek and
the sub-recent geological history of the Caracasbaai may be
arguments for regarding this area as potentially instable.
Although we are of the opinion that taking risks is associated with
and even necessary in human life, we can assure the reader that
during sampling of the limestones near Seroe Mansinga and
more especially when standing on the extreme tip near Lijhoek,
teeling the rocks slightly tremble under the impact of the waves,
we felt that this point, despite its fine views and the magnificent
landscape is not a good spot for building holiday houses, hotels
or other constructions!